The impact of expressive language development and the left inferior longitudinal fasciculus on listening and reading comprehension

Abstract

BackgroundDuring the first 3-years of life, as the brain undergoes dramatic growth, children begin to develop speech and language. Hallmarks of this progression are seen when children reach developmental milestones, forming the foundation of language. Expressive language milestones, such as the production of a child’s first word, are delayed in 5–8% of children. While for some children delays in reaching these milestones are harbingers of developmental disorders, for others expressive language delays appear to resolve. Regardless of whether or not early language skills appear resolved, difficulty with later comprehension is a likely outcome. Whether this heightened risk for poor comprehension differs based on text features, individual characteristics, or receipt of intervention remains unknown. Moreover, this relationship between expressive language development and comprehension is not yet linked to neurobiology, though the inferior longitudinal fasciculus (ILF) is a potential neurobiological correlate. Therefore, we investigated the impact of, and interactions between, expressive language development, early intervention, and the ILF on comprehension.MethodsLongitudinal recurrent survival analyses predicted the risk of answering a comprehension question incorrectly. Predictors of comprehension included expressive language development, passage features, participant characteristics, fractional anisotropy, receipt of early intervention, and later diagnosis of speech or language disorders.ResultsChildren with later expressive language milestones had poorer comprehension. When comprehension text features were examined, children with later milestones had poorer listening and reading comprehension, and poorer narrative and expository comprehension. The left ILF acted as a neurodevelopmental correlate, one that moderated the relationship between expressive language milestones and comprehension. Specifically, the left ILF exacerbated the relationship for those who did not receive early intervention and buffered the relationship for those who received intervention services. Early intervention decreased the risk of poor comprehension by 39% for children later diagnosed with a speech or language disorder.ConclusionsEarly intervention should be provided for children with delayed expressive language milestones, particularly those who are at risk for speech or language disorders. The ILF plays a critical role in the relationship between expressive language development and comprehension, which may be that of a protective factor for children with the most severe early issues with speech and language.

Functional and microstructural brain abnormalities, fatigue, and cognitive dysfunction after mild COVID-19

“…Pearson correlations were performed between the neuropsychological data and DTI parameters for specific tracts according to a priori hypothesis for each test, reducing the need to correct for multiple comparisons. For language, we investigated the correlation between phonological fluency and FA from ILF (Del Tufo, Earle, & Cutting, 2019); for the Trail Making Test, we investigated the association between the scores and the FA of right ILF, as previously investigated in healthy-aging individuals (Perry et al, 2009). However, we were aware of some dissociations of DTI parameters and cognitive impairment (for example, alterations of mean diffusivity without abnormality of FA (Goldstein et al, 2009)) and therefore explored the correlations between DTI indices (all four measurements) of both parahippocampal cingulae (right and left sides) and episodic memory.…”

Two Different Subcortical Networks of Language System: Morphogram and Phonogram, Through the Analysis of Unique Japanese Characters

“…The ILF connects the occipital and posterior occipito-temporal lobes with the temporal lobe, and it contributes to visual recognition and reading, while subserving the ventral semantic stream connecting the IFOF and SLF (Herbet et al 2018, Herbet et al 2019. Previous reports also mentioned the ILF associate with language networks, and the disruption of the ILF induced dyslexia (Herbert et al 2018, Del Tufo et al 2019). The electric cortical stimulation of the basal temporal language area induced kanji dyslexia, and the speci c area connects with a ventral stream via the ILF, which would contribute to the subcortical network of the kanji-reading process (Enatsu et al 2017).…”

Worldwide national intervention of developmental screening programs in infant and early childhood

“…For example, for children who have communication problems, more than 65% can be improved when intervention happens before 3 years of age [ 51 ]. Del Tufo et al [ 52 ] reported that early intervention decreased risk of poorer comprehension by almost 40%. In addition, they reported a positive association between receiving early intervention and expressive language development [ 52 ].…”

“…Del Tufo et al [ 52 ] reported that early intervention decreased risk of poorer comprehension by almost 40%. In addition, they reported a positive association between receiving early intervention and expressive language development [ 52 ].…”